Everybody on Earth is guilty of fouling the environment to some extent – to be alive, after all, is to be a polluter – but some of us are much worse offenders that others. And what’s true for individuals is true for countries. The African nation of Togo, for instance, has 3,500 cars, one for every 200 people. The US has 137 million cars, 35 percent of the world’s total, or one for every two residents, including people too young to drive.